1. Field of the Invention
The present invention is directed to a thermal coupling device which flexibly interfaces between a heat source and a heat sink.
2. Description of the Prior Art
Thermal coupling between a cryogenic refrigerator having a relatively fixed cold finger extending therefrom and a heat producing source such as an infrared detector is necessary in order to maintain the source at a predetermined temperature. Assemblies have been constructed which interface between a detector heat source and the cold finger sink and allow for misalignment so that the detector may be reoriented for optimum focus or tracking.
A prior art attempt to construct a coupling device is shown in U.S. Pat. No. 3,807,188. A coupling between a refrigeration source and a device to be refrigerated is mechanically accomplished at room temperature by a liquid metal-filled bellows between the refrigeration source and the device. In that coupling device, misalignment adjustments between the refrigerated cold finger and the movable detector must be made at room temperature. Thereafter, the cold finger is cryogenically cooled and the liquid metal-filled bellows freezes to provide the inter-engaging clamping force and the conductive thermal coupling.
In U.S. Pat. No. 3,889,119 a cryogenic cooler is described for an infrared receiver. A heat transfer mechanism is also shown which utilizes a flexible heat transfer strip connected between the end of a cold finger and a flanged member which abuts against the detector-vacuum module upon which the infrared detector is mounted. A biasing spring is also disclosed which surrounds the strip to bias the flanged member into engagement with the detector-vacuum module.